Feed mechanism overload release

ABSTRACT

A connecting link for transmitting linear motion along its axis to feed bore wedges of insulating material and having an overload release mechanism is disclosed. The connecting link consists of an outer link, and an inner link slidable relative to the outer link in the direction of transmission of the force. The inner link is provided with a recess and the outer link is provided with a spring loaded plunger arrangement which engages the recess and which yields allowing the relative sliding of the inner and outer links when the force being transmitted by the connecting link exceeds a predetermined value.

Umted States Patent 51 3,659,329 Walker May 2, 1972 [54] FEED MECHANISM OVERLOAD RELEASE Primary Examiner-Thomas H. Eager [72] Inventor: Robert G. Walker, Brighton, Mich. Atmmey jeffer8 and Rlcken [73] Assignee: lndustra Products, Inc., Fort Wayne, Ind. [57] ABSTRACT [22] Filed: Aug. 6, 1970 A connecting link for transmitting linear motion along its axis to feed bore wedges of insulating material and having an over- [211 App! 6168l load release mechanism is disclosed. The connecting link consists of an outer link, and an inner link slidable relative to the [52] U.S. CL... ..29/205E outer link in the direction f transmission f the f The [51] Int. Cl. ..H02k 15/00 inner link is provided with a recess and the Outer link is [58] Field Of Search R, D, E, R vided with a p i g loaded p g arrangement which gages the recess and which yields allowing the relative sliding [56] References cued of the inner and outer links when the force being transmitted UNITED STATES PATENTS by the connecting link exceeds a predetermined value. 2,873,514 2/1959 Mills ..29/205 E 5 Claims, 2 Drawing Figures PATENTEUMAY 2 I972 3, 659 329 I 2 I I Will INVENTOR ROBERT G. WALKER WAMM ATTORNEYS BACKGROUND OF THE INVENTION The present invention is concerned very broadly with the automatic manufacture of Dynamo Electric machinery and more especially with the forming and inserting of prewound coils and strips of insulating material in the magnetic members of such machines. Specifically, the present invention is concerned with a tension release in the mechanism which feeds the raw material of which the bore wedges for the stator of such a machine are to be fabricated. These bore wedges may be of the type illustrated in U.S. Pat. Nos. 2,283,146; 2,998,540; and 3,355,6l or as illustrated in the assignees copending application Ser. No. 770,643 and now U.S. Pat. No. 3,5 l9,862, dated July 7, I970. The last mentioned application also discloses a simple machine for fabricating such wedges. The wedges are generally automatically fabricated and inserted in a stator or other magnetic member by machines such as illustrated by U.S. Pat. No. 3,324,536, or by copending application Ser. No. 85,355, entitled Wedgemaker in the names of Robert G. Walker and'Donald E. Hill, filed Oct. 30, 1970.

Automatic machinery for fabricating such bore wedges is well known in the art. Such machinery is supplied by a reel containing the insulating material such as mylar. This material is fed for a definite length, cut, formed into a U-shape and then inserted in the magnetic member as illustrated more completely in the aforementioned copending application entitled Wedgemakerfiled Oct. 30, I970, Ser. No. 85,355.

It is not uncommon in such an automated fabrication process for the insulating material to become jammed at one stage in the process and while such jamming may by itself be a minor problem, the machine continues to run and continues to feed additional insulating material thus building up and compacting theinsulating material along the entire length of material routing resulting in a substantial log jam.

SUMMARY OF THE INVENTION It is a primary object of the present invention to provide an improved wedge maker which is not subject to the jamming and compacting of extensive amounts ofinsulating material.

The primary object of the present invention is achieved by providing a connecting link which transmits linear forces along its length from the source of power in an existing wedge making machine to the insulation feed mechanism of the existing wedge making machine and which fails to transmit energy between the power source and the insulation feed mechanism whenever a jamming of insulating material occurs along the fabrication route. Such jamming occurs due to variations in the width of the material as well as other imperfections in the material.

It is one object of the present invention to provide a connection link in a wedge making machine which prevents the stuffing and packing of insulating material in the event that some of the insulating material becomes jammed in the machine.

It is another object of the present invention to provide a force transmitting connecting link which fails to transmit any forces in excess ofa predetermined value.

It is a further object of the present invention to prevent possible machine damage by providing a feed mechanism tension release link.

It is yet another object of the present invention to provide a yieldable connecting link.

These and other objects and advantages of the present invention will appear more clearly from the following detailed disclosure read in conjunction with the accompanying drawmg:

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a top sectional view of a connecting link made in accordance with the teachings of the present invention; and

FIG. 2 is an exploded perspective view of the connecting link of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Turning first to the exploded perspective view of FIG. 2, the connecting link is seen to comprise an outer link 11 and an inner link 13. The outer link 11 is provided with an axial hole 15 ofa size to accept the shaft portion 17 on the inner link 13. Thus, the outer and inner links may thus far be seen to be freely slide one within the other, that is they are free to describe a linear motion. This relative motion of the two halves of the connecting link is prevented by a ball 19 which is forced into a recess 21 as is best seen in FIG. 1. This ball and recess together with the structure for holding the ball in the recess forms a release means which serves to prevent any linear motion between the members of the connecting link when the component of any forces being transmitted by that link in the direction of the sliding or linear motion of the outer link relative to the inner link is less than a predetermined value and this release means will yield allowing relative motion between the two link halves when that component force exceeds the predetermined value. The recess as shown in the drawings is optimumly located for a link which transmits a tension type of force and-if it were desired to transmit a compressional type force this recess would better be located at 21 so as to allow a substantial portion of the shaft 17 for sliding motion after the release means yields. In operation, one of the connecting points 23 would be connected to a source of power within the wedge making machine and the other of the connecting points 23 would be connected to the material feed portion of the machine.

Turning now to FIG. 1, that cross sectional view illustrates the entire connecting link overload release mechanism as assembled and in the position for best transmitting a tension type of force. The release means of the link comprises a recess 21 in the inner link into which a ball 19 is forced in the fashion of a spring loaded plunger mechanism. The spring loaded plunger mechanism itself comprises the ball 19 and a'plug 25 which together may be considered as equivalent to or replaceable by a plunger. The plunger along with a spring 27 and a set screw 29 are, held in place and at approximately right angles to the axis of relativemotion of the link halves by a detent holder 31 having a rim 33 at one end to hold the detent holder in the outer link and having a threaded portion 35 at the other end to accept the set screw. Thus, the entire spring loaded plunger mechanism consists of a holder, a plunger, a spring, and an adjustable set screw.

The yield point of the connecting link may be permanently altered by varying the depth of the recess 21 relative to the diamter of the ball 19, thus if the recess 21 exceeds the radius of the ball 19, the link will never yield in its proper fashion, whereas if the recess 21 is quite shallow the link will readily yield and indeed might yield on every stroke of the machine and never transmit energy to the feeding mechanism. The load point at which the link yields may also be adjusted by turning the set screw 29 so as to increase or decrease the tension caused by the spring 27 which in turn determines the force necessary to dislodge the ball 19 from the recess 21.

The steps necessary to assemble the connecting link should now be quite clear. The detent holder is first passed through the outer link so that the rim 33 seats in the corresponding rim provided on the inside of the connecting link. The outer and inner links may then be assembled, the ball and plug dropped into the detent holder, the spring inserted, and the set screw lastly inserted into the threaded portion of the detent holder. As an alternative assembly sequence after the detent holder is in place, the set screw may next be inserted, then the spring, plug, and ball dropped into the detent holder by the same route that the detent holder itself was placed in the outer link. At this point, the inner link is passed into its hole 15 until the ball snaps in place in the recess 21.

In the course of normal operation of the wedge making machine, the entire link transmits forces as though it were a solid piece, however, if an obstruction occurs, the feed mechanism encounters additional resistance which is sufficient to pop the plunger out of the recess 21 and on subsequent strokes of the machine, the outer and inner links merely slide relative to one another.

Thus, while the present invention has been described in reference to a specific embodiment, numerous modifications will suggest themselves to those of ordinary skill in the art. As just one example, the recess 21, while illustrated as a groove around the inner link, could equally well be formed as a simple circular hole in the side of the shaft portion 17. Accordingly, the scope of the present invention is to be measured only by that of the appended claims.

What is claimed is:

1. In an arrangement for winding and inserting coils and strips of insulating material wherein insulating material is fed for a definite length, cut, formed into a U-shape, and inserted in a magnetic member; a feed mechanism overload release comprising:

a first elongated member;

a second member adapted to be movably interconnected with said first member;

means limiting the relative motion said first and second members to a linear motion in the direction of elongation of said first member; and release means adapted to prevent said linear motion when the component of the forces being transmitted by said link in the direction of said linear motion is less than a predetermined value, and to yield allowing said linear motion when said component force exceeds said predetermined value whereby a blockage in the flow of insulating material actuates the feed mechanism overload release to prevent the feeding of additional insulating material.

2. The combination of claim 1 wherein said release means comprises:

a recess in one of said first and second members; and

a spring loaded plunger mechanism passing through the other of said members and adapted to yieldably engage said recess,

3. The combination of claim 2 wherein said spring loaded plunger mechanism comprises:

a holder, a plunger, a spring, and a set screw;

one end of said holder fixedly retained in said other member, said holder having an axis which is substantially perpendicular to said direction of elongation of said first member, the other end of said holder being provided with internal threads;

said plunger adapted to be forced into said recess by said spring and said spring tension being adjustably maintained by said set screw when said set screw is threaded into said other end of said holder.

4. The combination of claim 3 wherein said plunger comprises a ball and a plug, said ball engaging said recess and said plug engaging said spring and said ball.

5. The combination of claim 1 wherein said release means comprises aspring loaded plunger and a set screw, said set screw adapted to vary the spring tension and wherein said predetermined value may be selected by adjusting said set screw.

i k k k I 

1. In an arrangement for winding and inserting coils and strips of insulating material wherein insulating material is fed for a definite length, cut, formed into a U-shape, and inserted in a magnetic member; a feed mechanism overload release comprising: a first elongated member; a second member adapted to be movably interconnected with said first member; means limiting the relative motion said first and second members to a linear motion in the direction of elongation of said first member; and release means adapted to prevent said linear motion when the component of the forces being transmitted by said link in the direction of said linear motion is less than a predetermined value, and to yield allowing said linear motion when said component force exceeds said predetermined value whereby a blockage in the flow of insulating material actuates the feed mechanism overload release to prevent the feeding of additional insulating material.
 2. The combination of claim 1 wherein said release means comprises: a recess in one of said first and second members; and a spring loaded plunger mechanism passing through the other of said members and adapted to yieldably engage said recess.
 3. The combination of claim 2 wherein said spring loaded plunger mechanism comprises: a holder, a plunger, a spring, and a set screw; one end of said holder fixedly retained in said other member, said holder having an axis which is substantially perpendicular to said direction of elongation of said first member, the other end of said holder being provided with internal threads; said plunger adapted to be forced into said recess by said spring and said spring tension being adjustably maintained by said set screw when said set screw is threaded into said other end of said holder.
 4. The combination of claim 3 wherein said plunger comprises a ball and a plug, said ball engaging said recess and said plug engaging said spring and said ball.
 5. The combination of claim 1 wherein said release means comprises a spring loaded plunger and a set screw, said set screw adapted to vary the spring tension and wherein said predetErmined value may be selected by adjusting said set screw. 